Aminophosphonate compound, and application thereof in extraction of lithium in alkaline solution containing lithium ions

Abstract

The invention provides an aminophosphonate compound, and application thereof in extraction of lithium in an alkaline solution containing lithium ions, and relates to the technical field of metal ion extraction. The structure of the aminophosphonate compound is as shown in formula (I). In the formula (I), R1 is a straight chain of C1-C20 straight-chain or branched-chain alkyl, C1-C20straight-chain or branched-chain alkoxy, or C6-C10 aryl; R2 and R3 are respectively and independently hydrogen, C1-C10 straight-chain or branched-chain alkyl, C1-C10 alkoxy, or C6-C10 aryl; R < 3 > is hydrogen, C1-C10 straight-chain or branched-chain alkyl, C1-C10 alkoxy, or C6-C10 aryl; R4 and R are respectively and independently C1-C10 straight-chain or branched-chain, saturated or unsaturated, substituted or unsubstituted alkyl groups, or C6-C10 aryl; and n is an integer of 1-4. The aminophosphonate compound can be widely applied to extraction of lithium ions in the alkaline solution containing the lithium ions.

Description

technical field [0001] The invention relates to the technical field of metal ion extraction, in particular to an aminophosphonate compound and its application in extracting lithium from an alkaline solution containing lithium ions. Background technique [0002] Lithium is the lightest metal in nature and has strong electrochemical activity. Its metals and compounds are widely used in glass, ceramics, aluminum smelting, organic chemical industry, aerospace, nuclear fusion and other industries and fields as thermonuclear fusion (hydrogen bomb) explosives, high-performance propulsion fuels for aircraft, rockets and missiles, and shielding materials for nuclear reactors. [0003] At present, the effective methods of extracting lithium from salt lake brine include solvent extraction method, and the solvent extraction method inevitably adopts FeCl 3 As a co-extracting agent, the density of the extracted organic phase is increased, the density difference between the two phases is ...

AI Technical Summary

Problems solved by technology

[0003] At present, effective methods for extracting lithium from salt lake brine include solvent extraction, and solvent extraction inevitably uses FeCl3 as the The co-extraction agent increases the density of the extracted organic phase and reduces the density difference between the two phases. It requires high extraction and separation equipment. The traditional mixing and settling tank is difficult to meet the process requirements. High-efficiency centrifugal extraction equipment must be used, which is expensive; at the same time , after the introduction of FeCl3, it is very difficult to regenerate the extractant with alkali, and very precise flow control is required, otherwise it will cause problems such as a decrease in extraction rate or emulsification failure of the extractant

In addition, since the organic phase contains the co-extraction agent FeCl3, it is required that the extraction liquid (brine) must be kept weakly acidic, otherwise Fe will be hydrolyzed, and the brine entering the extraction section must be acidified , while lithium and boron generally exist together in salt lakes in the Qinghai-Tibet area of ​​my country, and boric acid must be precipitated during the acidification process, which needs to be filtered, so it is not applicable to the extraction of lithium in alkaline systems

Moreover, most of the extraction agents currently used for lithium can only achieve the separation of lithium and magnesium, and the extraction effect for alkali metal systems is very poor.

In short, due to the existence of the co-extraction agent FeCl3, the process flow is more complicated, the process control is very difficult, and the investment in equipment is large.

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